Injuries at a Water Slide -- Washington

On July 12, 1983, a new outdoor water slide consisting of two
fiberglass tubes 4 feet in diameter and 360 feet in length opened
in
Washington State. Sliders climbed 55 vertical feet to the
entrance,
where they jumped into a current of water and rode it through
either
tube, negotiating two 360-degree turns and two 45-degree drops
before
exiting into a splash pool.

From July 13 to August 31, 65 persons injured at this amusement
ride sought medical care in local physicians' offices and emergency
rooms and were reported to the County Emergency Medical Service.
The
slide operators reported that 178 patrons sought first aid at their
facility, of whom 10 (6%) were transported to a hospital. The rate
of
injury recorded by the slide operators was 8.1 per 10,000 rides
sold,
and the rate of medically treated injuries was 3.0/10,000.

The 65 medically treated sliders ranged in age from 8 years to
45
years. Age was unknown in one case. About equal numbers were aged
5-14 years, 15-24 years, and 25 years or older (Table 1); 42 (65%)
were female. Injuries included fractures, concussions, bruises and
abrasions, and sprains and strains (Table 1). Most concussions,
skull
and spinal fractures, lacerations, and "other injuries" occurred
among
females, while most sprains, strains, and "other fractures"
affected
males. For all injuries except concussions, the majority of
persons
were aged 15 years or older. All fractures occurred among persons
15
years of age or older. Of the nine spinal fractures, eight were
lumbar compression fractures and one was a fracture of the coccyx.
The "other fractures" were of the ribs in one case and of the
humerus
in the other. The sprains and strains were primarily back
injuries.
Of the 18 lacerations, 12 (67%) required sutures.

Interviews with 46 (71%) of the injured persons identified two
primary locations at which injuries occurred--the 45-degree drops
and
the final outlets. Of the 46, 32 (70%) reported being injured
while
going over the drops or shortly thereafter, either by landing on
the
buttocks or lower back or by being knocked off balance and thrown
against the sides of the tube; 11 (24%) were upended by the current
at
the outlet, striking their heads on the sharp-edged lip of the
tube.
The injuries occurred on the first or second ride in two-thirds of
the
46 cases.

The slide operators instituted several changes to reduce the
number of injuries, including removing a curve from one tube on
July
23, requiring every slider to wear a helmet on the first two rides
after August 1, rounding the edge of the outlet lip on August 12,
and
placing extra warning and instruction signs on August 31. Rates of
injury declined during July and early August, but rose again in the
latter half of August (Figure 1). Improvements in rates were not
closely related in time to the specific corrective measures taken.
No
slide-related injuries were reported by medical-care sources after
August 31.
Reported by S Marks, MD, C Hyatt, MD, Snohomish County, S Milham,
MD,
Epidemiology Section, Div of Health, Washington Dept of Social and
Health Svcs; Div of Field Svcs, Epidemiology Program Office,
Special
Studies Br, Chronic Diseases Div, Center for Environmental Health,
CDC.

Editorial Note

Editorial Note: Water slides are "recreational devices designed to
provide a descending ride into a splash-down pool at the base of
the
slide . . . by providing a flowing water film" (1). An estimated
600
are in operation in the United States, and operators of large
slides
may sell an estimated 500,000 tickets per year (2). In 1983,
according to the National Electronic Injury Surveillance System of
the
Consumer Products Safety Commission, water slides accounted for the
largest single share, 30% (2,941 cases), of injuries that occurred
at
amusement rides and were treated in emergency rooms in the United
States. Several water slide-associated fatalities have also been
reported (3).

Guidelines based largely on theoretical, engineering
considerations have been published for the structure and operation
of
water slides (1). There is yet no experience or empirical
knowledge
relating risks of injury to specific design features. The relative
severity of the injuries reported in this investigation--fractures
and
cerebral concussions in 25 (38%) of 65 cases--suggests that
excessive
speed and loss of body control occurred during the ride. These
factors and the association of injuries with two specific sections
of
the slide in 94% of cases interviewed suggest that design
considerations were important in this episode. Whether the rates
or
severity of injury at this slide are unusually high cannot be
determined without comparable studies at other sites.

There is no obvious explanation for the observed changes in
injury
rates over the summer. No alterations were made in the 45-degree
drop
sections of the course, and the curve that was removed was not
determined in patient interviews to be a high-risk location. The
use
of helmets and the rounding of the outlet lip are likely to have
reduced head injuries, lacerations, and abrasions, and the
proportion
of "repeaters" in the slider population, who had already
successfully
avoided injury and would be somewhat familiar with the course, may
have increased substantially during the season. These protective
considerations could have caused the early decline, but they were
still applicable when rates rose again in late August.

Whether the larger number of cases among females indicates a
higher injury rate for that sex is uncertain. Studies of swimming
pool and other aquatic injuries have found higher risks among males
(4) attributed to greater risk-taking behavior by males (5). The
prominence of older persons among fracture victims suggests that
larger body size and/or mass may be significant risk factors for
severe injury. To minimize risk, it may be necessary to make
special
considerations for sliders of greater size, weight, and age in the
design and/or admission guidelines for water slide rides.

Davis HF, et al. The 1990 objectives for the nation for injury
prevention: a progress review. Public Health Reports
1984;99:9-24.

DisclaimerAll MMWR HTML documents published before January 1993 are electronic conversions from ASCII text into HTML. This conversion may have resulted in character translation or format errors in the HTML version. Users should not rely on this HTML document, but are referred to the original MMWR paper copy for the official text, figures, and tables. An original paper copy of this issue can be obtained from the Superintendent of Documents, U.S. Government Printing Office (GPO), Washington, DC 20402-9371; telephone: (202) 512-1800. Contact GPO for current prices.

**Questions or messages regarding errors in formatting should be addressed to mmwrq@cdc.gov.